Hi, I'm new here. I have been rebuilding a 81 Yamaha XV750H. The issue that I am having is that with the factory cylinder head gasket sitting correctly in it's seat and the head torqued to the factory spec of 46ft-lbs, there is a gap of .030" between the cylinder and head. Has anyone else heard of this issue? Can I get a custom gasket made?

Have a look here:

https://www.tr1.de/pages/misc_shop.php

this should be exactly what you're looking for.

Cheers
Greg

Thanks for the help Greg, I will give it a shot. :thumb:

Sorry for putting some salt into this wound, but as far as i know Sepp has only Gaskets for the TR, which has a much bigger bore.
It is a known problem that there is a gap with the original gaskets, even worse with aftermarket stuff.
Putting the torque (with some grease on the tread, not to forget) to what yamaha says, is not enough. Give slightly  more torque - only what is necessary, not too much- wait over night, try again with a bit more  the next day and so on. That works more or less fine, i had to put my torque-wrench up to 78 mkg, don´t know how much ft-lbs that is,
regards Ali

Hi Ali, you are correct. I recieved an email reply from Sepp. He does not make or carry a gasket for the XV750 virago. Also, You mentioned in your post that you greased your studs and torqued your nuts, waited some time and repeated until you reached 78mkg? Is that correct? That would be 564 ft lbs and some. The Clymer service manual calls for 46 ft lbs. Did you mean 7.8 mkg?  That would make the finished torque at approximately 56 ft pounds. I am not sure how much I trust the material that the studs thread into on the case side. The studs themselves can handle plenty but not sure if they thread into a plethora of aluminum on the case side or if the engineers actually thought of steel thread inserts. Especially considering the nominal factory torque spec of 46 ft lbs (6.35 mkg).

Sorry, 78 Newtonmeter is correct, and yes, the studs should be greased , the yamaha manual says,
Regards Ali

Thanks again Ali, it seems that God continues to teach me patience. This time through a vintage motorcycle project. I tried cleaning the threads on the studs and nuts, and found that the nuts have a damaged or missing thread on all 4 of them, about 3 threads in. Also,  the NE brand head gasket that came in the "OEM spec" aftermarket complete gasket kit seem just way too thick. I tried molly grease on the threads and 57 ft lbs wich is 78 nm. The gap closed from .030" to .027" and I continue to see light from a flashlight looking down into the timing chain cover. I ordered and am going to wait for new Yamaha head gaskets and see if I can find the cylinder #2 head nuts. I am in the Seattle area. Does anyone know of a good source for these nuts? I think they are stainless. I am guessing that they are super rare and that I may need to go to a fastener specialty place and get something that is the same height as this also affects the engine mount geometry.  What would you guys do? If black steel is the only material nut I can find,  should I use the same amount of torque? Thanks again for your time and help.

Hello Mike, i can´t resist to answer, even if i cannot help and my technical english is poor.

I just measured a new TR1 aftermarket gasket , it has a thickness of 2,66 Millimeter.

What you can do to check the head is going correct onto the cylinder:
Just put it over the studs without a gasket , it should go down easiely without friction/resistance.
Sometimes the "collars" are too big in diameter, rusty or whatever, a bit of grinding with fine paper helps.
With the worn nuts: if you can´t get them, i have lots of them. Maybe later models of Yamaha V-Twins use the same dimension. And Yes, the height defines the mounting position, but you can use shims. One Millimeter more or less is not that important, as long as the nuts of each cylinder have the same height. And they are not really stainless, a good Quality (Steel) will work ,
Ali